src/write_http.c

   1 /**
   2  * collectd - src/write_http.c
   3  * Copyright (C) 2009       Paul Sadauskas
   4  * Copyright (C) 2009       Doug MacEachern
   5  * Copyright (C) 2007-2009  Florian octo Forster
   6  *
   7  * This program is free software; you can redistribute it and/or modify it
   8  * under the terms of the GNU General Public License as published by the
   9  * Free Software Foundation; only version 2 of the License is applicable.
  10  *
  11  * This program is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along
  17  * with this program; if not, write to the Free Software Foundation, Inc.,
  18  * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
  19  *
  20  * Authors:
  21  *   Florian octo Forster <octo at verplant.org>
  22  *   Doug MacEachern <dougm@hyperic.com>
  23  *   Paul Sadauskas <psadauskas@gmail.com>
  24  **/
  25
  26 #include "collectd.h"
  27 #include "plugin.h"
  28 #include "common.h"
  29 #include "utils_cache.h"
  30 #include "utils_parse_option.h"
  31 #include "utils_format_json.h"
  32
  33 #if HAVE_PTHREAD_H
  34 # include <pthread.h>
  35 #endif
  36
  37 #include <curl/curl.h>
  38
  39 /*
  40  * Private variables
  41  */
  42 struct wh_callback_s
  43 {
  44         char *location;
  45
  46         char *user;
  47         char *pass;
  48         char *credentials;
  49         int   verify_peer;
  50         int   verify_host;
  51         char *cacert;
  52         int   store_rates;
  53
  54 #define WH_FORMAT_COMMAND 0
  55 #define WH_FORMAT_JSON    1
  56         int format;
  57
  58         CURL *curl;
  59         struct curl_slist *headers;
  60         char curl_errbuf[CURL_ERROR_SIZE];
  61
  62         char   send_buffer[4096];
  63         size_t send_buffer_free;
  64         size_t send_buffer_fill;
  65         cdtime_t send_buffer_init_time;
  66
  67         pthread_mutex_t send_lock;
  68 };
  69 typedef struct wh_callback_s wh_callback_t;
  70
  71 static void wh_reset_buffer (wh_callback_t *cb)  /* {{{ */
  72 {
  73         memset (cb->send_buffer, 0, sizeof (cb->send_buffer));
  74         cb->send_buffer_free = sizeof (cb->send_buffer);
  75         cb->send_buffer_fill = 0;
  76         cb->send_buffer_init_time = cdtime ();
  77
  78         if (cb->format == WH_FORMAT_JSON)
  79         {
  80                 format_json_initialize (cb->send_buffer,
  81                                 &cb->send_buffer_fill,
  82                                 &cb->send_buffer_free);
  83         }
  84 } /* }}} wh_reset_buffer */
  85
  86 static int wh_send_buffer (wh_callback_t *cb) /* {{{ */
  87 {
  88         int status = 0;
  89
  90         curl_easy_setopt (cb->curl, CURLOPT_POSTFIELDS, cb->send_buffer);
  91         status = curl_easy_perform (cb->curl);
  92         if (status != CURLE_OK)
  93         {
  94                 ERROR ("write_http plugin: curl_easy_perform failed with "
  95                                 "status %i: %s",
  96                                 status, cb->curl_errbuf);
  97         }
  98         return (status);
  99 } /* }}} wh_send_buffer */
 100
 101 static int wh_callback_init (wh_callback_t *cb) /* {{{ */
 102 {
 103         if (cb->curl != NULL)
 104                 return (0);
 105
 106         cb->curl = curl_easy_init ();
 107         if (cb->curl == NULL)
 108         {
 109                 ERROR ("curl plugin: curl_easy_init failed.");
 110                 return (-1);
 111         }
 112
 113         curl_easy_setopt (cb->curl, CURLOPT_NOSIGNAL, 1L);
 114         curl_easy_setopt (cb->curl, CURLOPT_USERAGENT, PACKAGE_NAME"/"PACKAGE_VERSION);
 115
 116         cb->headers = NULL;
 117         cb->headers = curl_slist_append (cb->headers, "Accept:  */*");
 118         if (cb->format == WH_FORMAT_JSON)
 119                 cb->headers = curl_slist_append (cb->headers, "Content-Type: application/json");
 120         else
 121                 cb->headers = curl_slist_append (cb->headers, "Content-Type: text/plain");
 122         cb->headers = curl_slist_append (cb->headers, "Expect:");
 123         curl_easy_setopt (cb->curl, CURLOPT_HTTPHEADER, cb->headers);
 124
 125         curl_easy_setopt (cb->curl, CURLOPT_ERRORBUFFER, cb->curl_errbuf);
 126         curl_easy_setopt (cb->curl, CURLOPT_URL, cb->location);
 127
 128         if (cb->user != NULL)
 129         {
 130                 size_t credentials_size;
 131
 132                 credentials_size = strlen (cb->user) + 2;
 133                 if (cb->pass != NULL)
 134                         credentials_size += strlen (cb->pass);
 135
 136                 cb->credentials = (char *) malloc (credentials_size);
 137                 if (cb->credentials == NULL)
 138                 {
 139                         ERROR ("curl plugin: malloc failed.");
 140                         return (-1);
 141                 }
 142
 143                 ssnprintf (cb->credentials, credentials_size, "%s:%s",
 144                                 cb->user, (cb->pass == NULL) ? "" : cb->pass);
 145                 curl_easy_setopt (cb->curl, CURLOPT_USERPWD, cb->credentials);
 146                 curl_easy_setopt (cb->curl, CURLOPT_HTTPAUTH, CURLAUTH_ANY);
 147         }
 148
 149         curl_easy_setopt (cb->curl, CURLOPT_SSL_VERIFYPEER, (long) cb->verify_peer);
 150         curl_easy_setopt (cb->curl, CURLOPT_SSL_VERIFYHOST,
 151                         cb->verify_host ? 2L : 0L);
 152         if (cb->cacert != NULL)
 153                 curl_easy_setopt (cb->curl, CURLOPT_CAINFO, cb->cacert);
 154
 155         wh_reset_buffer (cb);
 156
 157         return (0);
 158 } /* }}} int wh_callback_init */
 159
 160 static int wh_flush_nolock (cdtime_t timeout, wh_callback_t *cb) /* {{{ */
 161 {
 162         int status;
 163
 164         DEBUG ("write_http plugin: wh_flush_nolock: timeout = %.3f; "
 165                         "send_buffer_fill = %zu;",
 166                         CDTIME_T_TO_DOUBLE (timeout),
 167                         cb->send_buffer_fill);
 168
 169         /* timeout == 0  => flush unconditionally */
 170         if (timeout > 0)
 171         {
 172                 cdtime_t now;
 173
 174                 now = cdtime ();
 175                 if ((cb->send_buffer_init_time + timeout) > now)
 176                         return (0);
 177         }
 178
 179         if (cb->format == WH_FORMAT_COMMAND)
 180         {
 181                 if (cb->send_buffer_fill <= 0)
 182                 {
 183                         cb->send_buffer_init_time = cdtime ();
 184                         return (0);
 185                 }
 186
 187                 status = wh_send_buffer (cb);
 188                 wh_reset_buffer (cb);
 189         }
 190         else if (cb->format == WH_FORMAT_JSON)
 191         {
 192                 if (cb->send_buffer_fill <= 2)
 193                 {
 194                         cb->send_buffer_init_time = cdtime ();
 195                         return (0);
 196                 }
 197
 198                 status = format_json_finalize (cb->send_buffer,
 199                                 &cb->send_buffer_fill,
 200                                 &cb->send_buffer_free);
 201                 if (status != 0)
 202                 {
 203                         ERROR ("write_http: wh_flush_nolock: "
 204                                         "format_json_finalize failed.");
 205                         wh_reset_buffer (cb);
 206                         return (status);
 207                 }
 208
 209                 status = wh_send_buffer (cb);
 210                 wh_reset_buffer (cb);
 211         }
 212         else
 213         {
 214                 ERROR ("write_http: wh_flush_nolock: "
 215                                 "Unknown format: %i",
 216                                 cb->format);
 217                 return (-1);
 218         }
 219
 220         return (status);
 221 } /* }}} wh_flush_nolock */
 222
 223 static int wh_flush (cdtime_t timeout, /* {{{ */
 224                 const char *identifier __attribute__((unused)),
 225                 user_data_t *user_data)
 226 {
 227         wh_callback_t *cb;
 228         int status;
 229
 230         if (user_data == NULL)
 231                 return (-EINVAL);
 232
 233         cb = user_data->data;
 234
 235         pthread_mutex_lock (&cb->send_lock);
 236
 237         if (cb->curl == NULL)
 238         {
 239                 status = wh_callback_init (cb);
 240                 if (status != 0)
 241                 {
 242                         ERROR ("write_http plugin: wh_callback_init failed.");
 243                         pthread_mutex_unlock (&cb->send_lock);
 244                         return (-1);
 245                 }
 246         }
 247
 248         status = wh_flush_nolock (timeout, cb);
 249         pthread_mutex_unlock (&cb->send_lock);
 250
 251         return (status);
 252 } /* }}} int wh_flush */
 253
 254 static void wh_callback_free (void *data) /* {{{ */
 255 {
 256         wh_callback_t *cb;
 257
 258         if (data == NULL)
 259                 return;
 260
 261         cb = data;
 262
 263         wh_flush_nolock (/* timeout = */ 0, cb);
 264
 265         curl_easy_cleanup (cb->curl);
 266
 267         if (cb->headers != NULL)
 268         {
 269                 curl_slist_free_all (cb->headers);
 270                 cb->headers = NULL;
 271         }
 272
 273         sfree (cb->location);
 274         sfree (cb->user);
 275         sfree (cb->pass);
 276         sfree (cb->credentials);
 277         sfree (cb->cacert);
 278
 279         sfree (cb);
 280 } /* }}} void wh_callback_free */
 281
 282 static int wh_write_command (const data_set_t *ds, const value_list_t *vl, /* {{{ */
 283                 wh_callback_t *cb)
 284 {
 285         char key[10*DATA_MAX_NAME_LEN];
 286         char values[512];
 287         char command[1024];
 288         size_t command_len;
 289
 290         int status;
 291
 292         if (0 != strcmp (ds->type, vl->type)) {
 293                 ERROR ("write_http plugin: DS type does not match "
 294                                 "value list type");
 295                 return -1;
 296         }
 297
 298         /* Copy the identifier to `key' and escape it. */
 299         status = FORMAT_VL (key, sizeof (key), vl);
 300         if (status != 0) {
 301                 ERROR ("write_http plugin: error with format_name");
 302                 return (status);
 303         }
 304         escape_string (key, sizeof (key));
 305
 306         /* Convert the values to an ASCII representation and put that into
 307          * `values'. */
 308         status = format_values (values, sizeof (values), ds, vl, cb->store_rates);
 309         if (status != 0) {
 310                 ERROR ("write_http plugin: error with "
 311                                 "wh_value_list_to_string");
 312                 return (status);
 313         }
 314
 315         command_len = (size_t) ssnprintf (command, sizeof (command),
 316                         "PUTVAL %s interval=%.3f %s\r\n",
 317                         key,
 318                         CDTIME_T_TO_DOUBLE (vl->interval),
 319                         values);
 320         if (command_len >= sizeof (command)) {
 321                 ERROR ("write_http plugin: Command buffer too small: "
 322                                 "Need %zu bytes.", command_len + 1);
 323                 return (-1);
 324         }
 325
 326         pthread_mutex_lock (&cb->send_lock);
 327
 328         if (cb->curl == NULL)
 329         {
 330                 status = wh_callback_init (cb);
 331                 if (status != 0)
 332                 {
 333                         ERROR ("write_http plugin: wh_callback_init failed.");
 334                         pthread_mutex_unlock (&cb->send_lock);
 335                         return (-1);
 336                 }
 337         }
 338
 339         if (command_len >= cb->send_buffer_free)
 340         {
 341                 status = wh_flush_nolock (/* timeout = */ 0, cb);
 342                 if (status != 0)
 343                 {
 344                         pthread_mutex_unlock (&cb->send_lock);
 345                         return (status);
 346                 }
 347         }
 348         assert (command_len < cb->send_buffer_free);
 349
 350         /* `command_len + 1' because `command_len' does not include the
 351          * trailing null byte. Neither does `send_buffer_fill'. */
 352         memcpy (cb->send_buffer + cb->send_buffer_fill,
 353                         command, command_len + 1);
 354         cb->send_buffer_fill += command_len;
 355         cb->send_buffer_free -= command_len;
 356
 357         DEBUG ("write_http plugin: <%s> buffer %zu/%zu (%g%%) \"%s\"",
 358                         cb->location,
 359                         cb->send_buffer_fill, sizeof (cb->send_buffer),
 360                         100.0 * ((double) cb->send_buffer_fill) / ((double) sizeof (cb->send_buffer)),
 361                         command);
 362
 363         /* Check if we have enough space for this command. */
 364         pthread_mutex_unlock (&cb->send_lock);
 365
 366         return (0);
 367 } /* }}} int wh_write_command */
 368
 369 static int wh_write_json (const data_set_t *ds, const value_list_t *vl, /* {{{ */
 370                 wh_callback_t *cb)
 371 {
 372         int status;
 373
 374         pthread_mutex_lock (&cb->send_lock);
 375
 376         if (cb->curl == NULL)
 377         {
 378                 status = wh_callback_init (cb);
 379                 if (status != 0)
 380                 {
 381                         ERROR ("write_http plugin: wh_callback_init failed.");
 382                         pthread_mutex_unlock (&cb->send_lock);
 383                         return (-1);
 384                 }
 385         }
 386
 387         status = format_json_value_list (cb->send_buffer,
 388                         &cb->send_buffer_fill,
 389                         &cb->send_buffer_free,
 390                         ds, vl, cb->store_rates);
 391         if (status == (-ENOMEM))
 392         {
 393                 status = wh_flush_nolock (/* timeout = */ 0, cb);
 394                 if (status != 0)
 395                 {
 396                         wh_reset_buffer (cb);
 397                         pthread_mutex_unlock (&cb->send_lock);
 398                         return (status);
 399                 }
 400
 401                 status = format_json_value_list (cb->send_buffer,
 402                                 &cb->send_buffer_fill,
 403                                 &cb->send_buffer_free,
 404                                 ds, vl, cb->store_rates);
 405         }
 406         if (status != 0)
 407         {
 408                 pthread_mutex_unlock (&cb->send_lock);
 409                 return (status);
 410         }
 411
 412         DEBUG ("write_http plugin: <%s> buffer %zu/%zu (%g%%)",
 413                         cb->location,
 414                         cb->send_buffer_fill, sizeof (cb->send_buffer),
 415                         100.0 * ((double) cb->send_buffer_fill) / ((double) sizeof (cb->send_buffer)));
 416
 417         /* Check if we have enough space for this command. */
 418         pthread_mutex_unlock (&cb->send_lock);
 419
 420         return (0);
 421 } /* }}} int wh_write_json */
 422
 423 static int wh_write (const data_set_t *ds, const value_list_t *vl, /* {{{ */
 424                 user_data_t *user_data)
 425 {
 426         wh_callback_t *cb;
 427         int status;
 428
 429         if (user_data == NULL)
 430                 return (-EINVAL);
 431
 432         cb = user_data->data;
 433
 434         if (cb->format == WH_FORMAT_JSON)
 435                 status = wh_write_json (ds, vl, cb);
 436         else
 437                 status = wh_write_command (ds, vl, cb);
 438
 439         return (status);
 440 } /* }}} int wh_write */
 441
 442 static int config_set_string (char **ret_string, /* {{{ */
 443                 oconfig_item_t *ci)
 444 {
 445         char *string;
 446
 447         if ((ci->values_num != 1)
 448                         || (ci->values[0].type != OCONFIG_TYPE_STRING))
 449         {
 450                 WARNING ("write_http plugin: The `%s' config option "
 451                                 "needs exactly one string argument.", ci->key);
 452                 return (-1);
 453         }
 454
 455         string = strdup (ci->values[0].value.string);
 456         if (string == NULL)
 457         {
 458                 ERROR ("write_http plugin: strdup failed.");
 459                 return (-1);
 460         }
 461
 462         if (*ret_string != NULL)
 463                 free (*ret_string);
 464         *ret_string = string;
 465
 466         return (0);
 467 } /* }}} int config_set_string */
 468
 469 static int config_set_boolean (int *dest, oconfig_item_t *ci) /* {{{ */
 470 {
 471         if ((ci->values_num != 1) || (ci->values[0].type != OCONFIG_TYPE_BOOLEAN))
 472         {
 473                 WARNING ("write_http plugin: The `%s' config option "
 474                                 "needs exactly one boolean argument.", ci->key);
 475                 return (-1);
 476         }
 477
 478         *dest = ci->values[0].value.boolean ? 1 : 0;
 479
 480         return (0);
 481 } /* }}} int config_set_boolean */
 482
 483 static int config_set_format (wh_callback_t *cb, /* {{{ */
 484                 oconfig_item_t *ci)
 485 {
 486         char *string;
 487
 488         if ((ci->values_num != 1)
 489                         || (ci->values[0].type != OCONFIG_TYPE_STRING))
 490         {
 491                 WARNING ("write_http plugin: The `%s' config option "
 492                                 "needs exactly one string argument.", ci->key);
 493                 return (-1);
 494         }
 495
 496         string = ci->values[0].value.string;
 497         if (strcasecmp ("Command", string) == 0)
 498                 cb->format = WH_FORMAT_COMMAND;
 499         else if (strcasecmp ("JSON", string) == 0)
 500                 cb->format = WH_FORMAT_JSON;
 501         else
 502         {
 503                 ERROR ("write_http plugin: Invalid format string: %s",
 504                                 string);
 505                 return (-1);
 506         }
 507
 508         return (0);
 509 } /* }}} int config_set_string */
 510
 511 static int wh_config_url (oconfig_item_t *ci) /* {{{ */
 512 {
 513         wh_callback_t *cb;
 514         user_data_t user_data;
 515         char callback_name[DATA_MAX_NAME_LEN];
 516         int i;
 517
 518         cb = malloc (sizeof (*cb));
 519         if (cb == NULL)
 520         {
 521                 ERROR ("write_http plugin: malloc failed.");
 522                 return (-1);
 523         }
 524         memset (cb, 0, sizeof (*cb));
 525         cb->location = NULL;
 526         cb->user = NULL;
 527         cb->pass = NULL;
 528         cb->credentials = NULL;
 529         cb->verify_peer = 1;
 530         cb->verify_host = 1;
 531         cb->cacert = NULL;
 532         cb->format = WH_FORMAT_COMMAND;
 533         cb->curl = NULL;
 534         cb->headers = NULL;
 535
 536         pthread_mutex_init (&cb->send_lock, /* attr = */ NULL);
 537
 538         config_set_string (&cb->location, ci);
 539         if (cb->location == NULL)
 540                 return (-1);
 541
 542         for (i = 0; i < ci->children_num; i++)
 543         {
 544                 oconfig_item_t *child = ci->children + i;
 545
 546                 if (strcasecmp ("User", child->key) == 0)
 547                         config_set_string (&cb->user, child);
 548                 else if (strcasecmp ("Password", child->key) == 0)
 549                         config_set_string (&cb->pass, child);
 550                 else if (strcasecmp ("VerifyPeer", child->key) == 0)
 551                         config_set_boolean (&cb->verify_peer, child);
 552                 else if (strcasecmp ("VerifyHost", child->key) == 0)
 553                         config_set_boolean (&cb->verify_host, child);
 554                 else if (strcasecmp ("CACert", child->key) == 0)
 555                         config_set_string (&cb->cacert, child);
 556                 else if (strcasecmp ("Format", child->key) == 0)
 557                         config_set_format (cb, child);
 558                 else if (strcasecmp ("StoreRates", child->key) == 0)
 559                         config_set_boolean (&cb->store_rates, child);
 560                 else
 561                 {
 562                         ERROR ("write_http plugin: Invalid configuration "
 563                                         "option: %s.", child->key);
 564                 }
 565         }
 566
 567         ssnprintf (callback_name, sizeof (callback_name), "write_http/%s",
 568                         cb->location);
 569         DEBUG ("write_http: Registering write callback '%s' with URL '%s'",
 570                         callback_name, cb->location);
 571
 572         memset (&user_data, 0, sizeof (user_data));
 573         user_data.data = cb;
 574         user_data.free_func = NULL;
 575         plugin_register_flush (callback_name, wh_flush, &user_data);
 576
 577         user_data.free_func = wh_callback_free;
 578         plugin_register_write (callback_name, wh_write, &user_data);
 579
 580         return (0);
 581 } /* }}} int wh_config_url */
 582
 583 static int wh_config (oconfig_item_t *ci) /* {{{ */
 584 {
 585         int i;
 586
 587         for (i = 0; i < ci->children_num; i++)
 588         {
 589                 oconfig_item_t *child = ci->children + i;
 590
 591                 if (strcasecmp ("URL", child->key) == 0)
 592                         wh_config_url (child);
 593                 else
 594                 {
 595                         ERROR ("write_http plugin: Invalid configuration "
 596                                         "option: %s.", child->key);
 597                 }
 598         }
 599
 600         return (0);
 601 } /* }}} int wh_config */
 602
 603 static int wh_init (void) /* {{{ */
 604 {
 605         /* Call this while collectd is still single-threaded to avoid
 606          * initialization issues in libgcrypt. */
 607         curl_global_init (CURL_GLOBAL_SSL);
 608         return (0);
 609 } /* }}} int wh_init */
 610
 611 void module_register (void) /* {{{ */
 612 {
 613         plugin_register_complex_config ("write_http", wh_config);
 614         plugin_register_init ("write_http", wh_init);
 615 } /* }}} void module_register */
 616
 617 /* vim: set fdm=marker sw=8 ts=8 tw=78 et : */